$i = \sqrt{-1}$

Example · High school

Terms

Term	This example	Why
algebraic number	✓	$i$ is algebraic, because it is a root of $x^2 + 1$, so it is not transcendental.
real number	✗
rational number	✗	$i$ not rational because is not a real number.
irrational number	✗	$i$ is not irrational because is not a real number.
transcendental number	✗

Distinctions using this example

• Rational vs. irrational vs. algebraic vs. transcendental numbers

All examples · All distinctions · All definitions